In precision optics

LEITZ

FLUORESCENCE

ILLUMI1NATINGEQ UIPM4ENT

The accelerated interest in fluo-

rescence microscopy in various

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sible by the new fluorescence

accessories. The source is a CS

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A reputation for integrity and a- tradition of service have led thousands of scientific

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E. LEITZ, INC., Dept. SC-Il468 Fourth Avenue, New York 16, N.Y. I

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NNAMESTREET

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E. LEITZ, INC., 468 FOURTH AVENUE, NEW YORK 16, N. V.

Distrlbutors of the world-famous products of Ernst Leitz, Wetzlar, Germany

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1 155S

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a study of resistance to infectious diseaseand the behavior of antiserums

IMMUNOLOGY and SEROLOGYBy Philip L. Carpenter

This new book explains what is currently known about immunology and serology.It studies resistance to infectious disease and the properties and behavior ofantibodies formed within an animal in response to foreign antigenic substances.

To bacteriologists, botanists, zoologists, criminologists, and students, this bookoffers the helpful tools which assist in classification of bacteria, plants and animalsand the identification of their components.

ANEW

SAUNDERSBOOK

By PHILIP L. CARpWN-TER, Professor of Bac-teriology, University ofRhodeIsland. 351 pages,6%1 x 9X4¼", illustrated.

Neu-

Ready in January!

Controversial material is presented so that the student can see the field is youngand what developments lie ahead. The author covers nature of infectious disease,normal protection, susceptibility, types of immunity, laboratory production ofantiserums, chemical nature of antibodies, the role of lymphoid tissues and plasmacells in antibody formation, response to antigenic stimuli and the Rh factor.Antigens are fully discussed-classes, detection, properties and active chemicalgroups. Many tables and diagrams clarify test results, reactions and structures.

To provide familiarity with various technical procedures and to illustrate funda-mental principles a 27-page appendix describes experiments in serology. Methodsare carefully detailed in the first few sections, but as the student masters thefundamental techniques directions are given in briefer form.

CONTENTSInfection and ImmunityThe Immune ReactionsAntigensSerum ProteinsProduction of AntibodyThe Anigen-Antibody ReactionPrecipitationAgglutination

IsohemagglutinationToxins and AntitoxinsPhacocytosisCytolysis and Complement FixationAntiviral ImmunityAllergyAppendix-Experiments in SerologyIndex

W. B. SAUNDERS COMPANY

West Washington Square Philadelphia 5

SCIENCE is published weekly by the AAAS, 1515 Masachusetts Ave., NW, Washington 5, D.C. Entered at the Lancaster, Pa., Post Office as second clsmatter under the act of 3 March 1879. Annual subscriptions: $7.50; foreign postage, $1; Canadian postage, 50¢.

25 NOVEMBER 1955 995

Black-light provides a versatile toolfor the arts and sciences-in industry,research, medicine, biology andcriminology. Manifold uses arerapidly being extended, new technicsdevised in many investigativedirections-

Questions and answers help clarify terminologyQuestion: What is Black Light?Answer: It is a name applied to invis-ible ultra violet light, the band of en-ergy between the visible and x-ray re-gion of the spectrum.Questions: What are the regions of vis-ible light in Angstroms? In Microns?Answer: An angstrom is equal to 1/250millionth of an inch. A micron is equalto 10 angstrom units.Question: How many types of ultra vio-let energy are there?Answer: Broadly speaking, there arethree-short wave, middle and longwave.Question: What is short wave ultraviolet?Answer: It is that portion of the spec-trum from 1850 angstroms to 2800angstroms-also known as far ultraviolet. It includes the 1850A bandwhich produces ozone, and the 2537Aband, known as the "germicidal band",which effectively destroys airborne bac-teria, or surface bacteria of molds.Question: What is middle ultra violet?Answer: Middle ultra violet extendsfrom 2800A to 3200A. It includes thepeak "suntan" band of 2967A, the re-gion producing the maximum source ofVitamin "D". Sun "tan" is due to thisband of energy in sunlight, and pro-duced by sun lamps. It does not pro-duce useful fluorescence.

Question: What does the long wave in-clude?Answer: Long wave covers 3200A to3900A, also- known as near ultra-violetor Wood's light, below the usual lowerlimit of human perception at 4000A.Question: Which wave length is mostuseful to produce fluorescent responses?Answer: Long wave ultra violet, suit-ably filtered to exclude visible radia-tion.Question: Why is a filter necessary?Answer: Specially compounded filterstransmit essential "fluorescent" wavelengths, and cut off extraneous visibleenergy.Question: Why do we see blue light ifultra violet is supposed to be invisi-ble?Answer: We see usually only the resultwhen Black Light impinges on the sub-ject material which, in turn, respondswith fluorescence. This fluorescence, inorder to be visible, occurs in the region4000 to 7800A. Filters do not quite cutoff sharply at 4000A. Hence we see asmall amount of visible violet-blue.Question: What is fluorescence?Answer: Fluorescence is the visiblelight given off by an object ilmuminatedby black light-the result of a shift inwave length caused by the shorter-than-visible energy reflection beingconverted to longer wave lengths.

Question: Why are some materialsfluorescent and some not?Answer: Some authors attempt to listfluorescent materials, which would filla large book. For example, in examin-ing a surface to determine whether in-visible mold spores have begun theirgrowth, the material ordinarily wouldbe non-fluorescent, but the presence ofmold spores causes a pinkish, spottyfluorescence.Question: What are the colors of fluor-escence?Answer: Any color of the spectrum ora combination thereof.Question: Is 3660A ultra violet harmfulto eyes or skin?Answer: Authorities assert it is notharmful. Complaints against BlackLight are usually psychological. Ap-parent discomfort is caused by naturalfluorescence of surfaces of the humaneye, causing a sensation of fuzziness,sometimes annoying, but no proof thatit is harmful is extant.

In industry, product inspection andidentification is the greatest use ofBlack LightEach industry or process develops its own

technic. A few uses will exemplify others:-todetect cracks, flaws and other defects in metals,castings, ceramics, and plastics. The part isdipped in fluorescent dye, which penetrates thecracks or fills the flaws. The part is next washedto remove the surface dye, then examinedunder Black Light. Defects are immediatelyapparent. Leaks in gas or hydraulic lines canbe checked by injecting fluorescing materialinto the system.

Since 1894996

* A. DAIGGER and COMPANYSCIENCE, VOL. 122

Ultra-Violet LLIgh

Fluorescent tracers in powder form may beadded to slurries so that the proper coverage ofcoatings may be later evaluated under BlackLight. Powders may be added to rubber com-positions or paper pulp.

If invisible marking is desirable to date aproduction run, as on bags, paper or cloth, in-visible inks can be used. These become visibleonly under Black Light. Black Light applica-tions are infinite, using powders, inks, greases.

Uses in criminologyIn criminology, fluorescence of parts of the

anatomy is used to identify victims of amnesia,or will aid in the identification of bodies. Scartissue which might be invisible under normallight shows up under Black Light. Outlines ofbirthmarks or tattoos which may have been re-moved are often visible under Black Light.

Fluorescent powders are sometimes used todust valuable merchandise. This powder, norm-ally invisible, will transfer freely to a thief'shands, clothing, or automobile, and examina-tion under Black Light will tell the tale.Fluorescent powders are also used to mnrkpaper money; coins may be marked withinvisible fluorescent lacquer.

Typical uses in medicineIn medicine, for example, Black Light is em-

ployed in urinalysis and other clinical proce-dures. Fluorescent staining is used in micro-scopy for tissue differentiation. Fluorescein inthe anterior area of the eye provides a rapidmeans of detecting foreign bodies under Black

Spectrogram of BlackLights. Note broad con-tinuum of radiation, afeature of conversionphosphor-coated sourcetube. Transmission curvebelow is for envelopefilter used in Black Lights.Note peak at 3660Aand cut-off of uselessoutput. Full-filteredHARMLESS radiant en-ergy produces maximumfluorescence response inobserved materialsWITHOUT head andglare characteristic ofother sources.

I l Angstrom units3121 3660 4078 4350

Light. Corneal lesions, abrasions and ulcers arealso easily seen. Many skin conditions ordiseases of the skin and scalp are seen moreclearly orbecome visible only under Black Light.Additional data on medical applications is givenin BuUetin 542.

Examples of other usesStamps, rare books, prints, pictures, may be

examined under Black Light, which divulgesmarkings and tell-tale differences, otherwise in-visible. Insects examined under Black Lightshow marked characteristics. Tracer dyes, inksand greases will further aid in entomology,anatomical and physiological studies. Tracing

rodents is done by droppings caused to fluoresceby adding special material into foodstuffs. In-troduction of tracer powders into wash waterswill help check cleanliness of dishes, pots orpans. Identification of batches of grain andother foodstuffs, by introducing fluorescenttracers, is easily performed.

Prices, lot numbers, special batches, designson fabrics, dates,-even personnel identitycan be indicated by tracers that become visibleunder Black Light.Almost every science is aided by the use of

Ultra Violet Black Light, to demonstrate char-acteristics not seen under visible light. Potentialapplications are virtually innumerable.l_f. w~~~~~~~~~~r

40744070 4080 40

Data for orderingstandard model black lights

4070 ULTRA VIOLET-MAGNIFIER COMBINATIONon laboratory stand with universal joint; finger-tip adjustment to any angle, from table level to15" above. Lighting head removable. Completewith ultra violet tubes for 115 volts A.C. 38.00

4072 ULTRA VIOLET "WOODS" LIGHT. Compact,light weight unit, with two General Electrictubes. Produces high output of 3660 A.U. ultra-violet. Corning glass filters screen out mostvisible light. Weighs less than 14 oz. Bakelitecase, easy-to-clean, 6Y2 x 3Y2". For 115 volts

A.C .22.754074 TWIN TUBE ULTRA-VIOLET AND MAGNIFIERCOMBINATION. Ideal for professional, experi-mental, industrial, scientific uses. Enlarges theimage three-fold. One tube on each side of thelens provides a flood of fluorescing ultra-violet.Ground, polished rectangular lens 4" x 2". Focallength permits use of hands or instruments

under the lens. Bakelite housing 634" by 5Y2".For 115 volts A.C ................. 30.00

4076 CRIMINOLOGY KIT. For investigation andlaw enforcement agencies. Looks like a lunchbox to avoid suspicion. Batteries and tracer ma-terials store in lower part of case, probe typeblack light in upper. Operates from batteriessupplied, or from 115 volts A.C. Produces 3660Aenergy, harmless wave length of maximum

fluorescent response in all materials; will passfreely through all types of glass. Case 5 x 7 x 10",weight 7 lbs. Complete ............... 39.50

4078 BLACK LIGHT FOR QUALITY CONTROL,industrial inspections, arts, sciences-in reflec-tor fixtures for illumination of inspection areas,displays, stages, special effects. Available inseveral different lengths or with germicidaltubes to kill air-borne bacteria in offices, fac-tories, hospitals. Full details in Bulletin 542.

4080 UVILUX BLACK LIGHT. Powerful, high in-tensity, peak efficiency long wave Ultra Violetsource (at 3660Angstrom Units) for every pro-fessional requirement ... generated by a 100Watt sealed beam reflector-type mercury quartzarc. Heat resistant filter excludes most visiblelight. Converts from a hand-held to a directivebase-mounted unit; stays positioned withoutmanipulation. For 115 volts A.C. With singlefilter 82.50

Would you like to receivefree copies of theDAIGGER APPARATUS DIGEST?

Write on your letterhead,mentioning your title and kindof scientific work you do.

157 West Kinzie Street a

25 NOVEMBER 1955Chicago 10, Illinois

997

4078

0

500 cc. ionization chamber may be positioned up to

100 ft. from operator permitting continuous monitoring

of high radiation intensity without hazard to personnel.

NUCILEAR-CHICAGO'S NEW "'CUTIE PIE"

for Beta, Gamma and X-ray monitoringThis all new "Cutie Pie" provides high speed, accuratemeasurement of beta, gamma, and x-ray field intensities-is ideal for personnel protection, industrial radiographyuses, decontamination procedures, or remote monitoring.A large 0.7 mg/cm2 window covers the entire end of

the chamber and permits measurement of beta energiesdown to 50 KEV with good REP calibration. Beta sensi-tivity is such that one microcurie of carbon-14 gives a

full scale deflection on the low (25 mr/hr) range.

A window shield is provided to cut out betas whenreading only gammas or x-rays. Operation switch in-

cludes three ranges to 2500 mr/hr, zero set, and batterycheck positions. All critical components are hermeticallysealed, assuring highest degree of stability and accuracy.

Special retractable legs and extreme light weight give thisunit an operating convenience unmatched by any othersimilar instrument on the market. Write today for fullinformation.

*Gamma ray energy dependence is linear within + 10%from 50 KEV to 2 MEV.

X t~~~~~~~~Fb_wNuclear Instrument and Chemical Corporation237 West Erie Street, Chicago 10, Illinois

LEADERS IN MAKING RADIOACTIVITY COUNT

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All your laboratory needs can betaken care of quickly, at lowestcost when you buy Precision equip-ment. Over 1500 items are avail-able from Precision to meet yourevery requirement.And you can be sure of long, de-pendable service from Precisionequipment because we make theitems we sell. Quality control inour factory plus Precision manufac-turing efficiency assure you of topperformance. Write us for descrip-tive bulletins.

IMMEDIATE DELIVERY ON THESE ITEMS:

Hi-Speed CentrifugeRheostat controlledspeeds 1800-5000 rpmsuitable for micro andsemi-micro analysis,and difficult chemicalseparations. Holdseight 15 ml straight ortapered tubes. Adap-ters for 1/2 to 5 mltubes. Data sheet 204 a

Heaters and Hot -PlBuilt specifically forlab service. High qual-ity porcelain refractorytops. Provisions forapparatus set-ups onheaters. Two adjust-able heat types: Ful-Kontrol with auto-transformer controlfrom 0 to 750 wattsand Type RH withbuilt-in rheostat. Cata-log 600.

Mag-Mix StirrersMa&netically agitateliquids under pressure,in vacuum. Mix vis-cous liquids. Stirbatches of test tubessimultaneously. Rheo-stat controlled speedranges. Two electricmodels, one air modelfor safe use with flam-mable liquids. Bulle-tins 590-R and 595-

ates

Micro-Set Thermo-Regulators

Control temperature within verynarrow limits (models as sensitive as0.005°F). Operate electrical relay which

controls heating elements, etc. Tempera-ture setting may be pre-set or changed.Range spans as wide as -35 to +500°F.Bulletin 647A.

3739 West Cortland StreetChicago 47

SCIENCE, VOL. 122

TITROMETER SUPERIOMRITY

i FIVE WAYS!

PRECISION-SHELLDUAL-TITROMETER

GIVES WIDERAPPLICATION

THAN ANY OTHER

* WIDEST TOTAL RANGE

* MOST SENSITIVE CIRCUIT

* CONCURRENT TITRATIONS

* REVERSIBLE POLARITY

* GREATEST ACCURACY FOR

NON-AQUEOUS TITRATIONS

WIDEST APPLICATIONAn unequalled range of minus 1650 to plus 1650 millivoltsmakes possible certain titrations, particularly oxidation-reductions not within the scope of other instruments. Thisrange combined with superior sensitivity (10-13 amps) of-fers the analyst an instrument capable of performing everypotentiometric titration-aqueous or non-aqueous.

"MAG-MIX" MAGNETIC STIRRERSThese offer infinite control from a "barely-turning" speedto vigorous churning action. Eliminates a glass stirrer rodfrom the cleaning operation between titrations.

DUAL TITRATION INCREASES OUTPUTThe analyst can run two different titrations at the sametime-can almost double his work output. He simply switchesa knob to change from the left to the right side.

UNEQUALLED PERFORMANCEThe Precision-Shell Dual-Titrometer combines wide rangeand sensitivity with the ability to indicate directly to 2millivolts or .05 pH. The dial is such that interpolation toone millivolt-even less-is immediately possible.

Write for bulletin No. 615.for detailed information.

IN STOCKFOR IMMEDIATE DELIVERY

25 NOVEMBER 1955

SUPERIOR SENSITIVITYScale readings are easy because only 250

millivolts are actually included on the indi-cator dial. This makes the band narrowenough to clearly see as small a change as 10millivolts. The needle actually moves at least3 times as far in response to any potentialchange as it will on any other titrometer.

"pp

3739 WEST CORTLAND STREET * CHICAGO 47

999

U J]('lb II1tLiJ~VE I

for Partition Chromatographyand Paper Electrophoresis

A photoelectric- precision instrument for the rapidand convenient evaluation of strips and sheetsof filter paper in partition chromatography andpaper electrophoresis.

SCIENCE, VOL. 122

PHOTOVOLIT Line-OperatedMultiplier FLUORESCENCE METER

Mod. 540

* High-sensitivity for measurement of low concentrations(full-scale setting for 0.001 microgram qui,nine sulphate)

* Micro-fluorimetry with liquid volumes as low as 1 ml* Low blank readings, strict linearity of instrument response* Universally applicable due to great variety of available fil-

ters, sample holders, adapters and other accessories* Interference filters for high specificity of results and for

determining spectral distribution of the fluorescent light* High-se,nsitivity nephelometry for low degrees of turbidities* Fluorescence evaluation of powders, pastes, slurries, and

solids, also for spot-tests on filter paper without elutionWrite for Bulletin #392 to

0E F K~~1

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Which of these

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Reveals finest detail in bright, clear, easy-to-see images.Color-corrected lOX and 43X objectives; flat fields minimize distortion.Saves time now with pre-focusing gage. Saves time later because it'sstandard size, standard operation... nothing to unlearn. More teachingadvantages than any pther student microscope, at any price.

/BAUSCH & LOMB MODEL LRMBALOPTICON PROJECTOR

Opens students' minds to quick comprehension ... with vivid screen-

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/BAUSCH & LOMB TRIPLE-PURPOSEM CRO-PROJECTOR

Unlocks the micro-world for observation by your entire

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'_~~~~~~*SGet helpful data on B&L visual teaching instrumentsWrite for demonstration and Catalog E-152.Bausch & Lomb Optical Co., 64279 St. Paul St.,Rochester 2, N. Y.

SCIENCE, VOL. 122

MI

- 4wIMNOWWOWRWAWAM

1002

.....

Medical lResearchA MIDCENTURY SURVEYPublished for the American Foundation

by Little, Brown & Company

Comments onMEDICAL RESEARCH:

WALTER BAUER -,"A superb jobin reviewing accurately all thepertinent information about therheumatic syndromes."W. M. STANLEY "The chapteron viruses does a wonderful job. .. useful to investigators aswell as to practitioners."ESMOND R. LONG "The chap-ter on tuberculosis is a remark-able achievement."RALPH W. GERARD "The schi-zophrenia chapter is certainlya balanced, comprehensive, wellorganized and well presentedsummary of the over-all statusof schizophrenia research andthought."1. L. CHAIKOFF "An excellentjob in assembling current con-cepts on arteriosclerosis and theevidence in support of theseconcepts."GEORGE A. PERERA -"The chap-ter on hypertension is a superbpresentation of developingknowledge of mechanisms in-volved in normal and abnormalblood pressure."M. C. WINTERNITZ "The chap-ter on cancer is a colossal task,beautifully accomplished."MARK KELLER- "The chapter onalcoholism accomplishes withexceptional skill the difficulttask of reviewing comprehen-sively a field involving multi-ple branches of science."TRUMAN G. SCHNABEL -"Thesetwo volumes are amazing inscope and revelation. Cliniciansgenerally will salute them."

25 NQVEMBER 1955

AMERICAN MEDICAL RESEARCHin principle and practice

UNSOLVED CLINICAL PROBLEMSin biological perspective

Foreword by CURTIS BOK, ChairmanIntroduction by ESTHER EVERETT LAPE,Member in Charge, The American Foundation

VOLUME I. American Medical Research in principle andpractice defines medical research as rooted in biology,implying contributions from chemistry, physics, mathe-matics. The volume discusses the relation of medicalresearch to medical education. It illustrates the contribu-tions of various research agencies (universities, medicalschools, foundations, research institutes, national volun-tary health societies, industry, government). The con-cluding chapter discusses the ways and means of control-ling the products of medical research: patents, federalcontrols; standardizing influence of professional groups.VOLUME II. Unsolved Clinical Problems in biologicalperspective discusses contributions from basic researchto cancer, infertility, arteriosclerosis, hypertension, rheu-matic syndromes, tuberculosis, viruses, chronic alcohol-ism and schizophrenia.

Committee of ConsultantsWALTER BAUER * GEORGE H. BISHOP * AUSTIN M. BRUES* GEORGE W. CORNER* RENE J. DUBOS * C. A. ELVEHJEM* LOUIS F. FIESER * THOMAS FRANCIS, JR. * RALPH W.GERARD * MICHAEL HEIDELBERGER * WILLIAM G. LENNOX* ESMOND R. LONG * WILLIAM S. MCCANN * THOMASPARRAN * LINUS C. PAULING * JOHN P. PETERS * I. S.RAVDIN * FRANCIS 0. SCHMITTe* TRUMAN G. SCHNABEL* W. M. STANLEY * DEWITT STETTEN, JR.* E. L. TATUM* STAFFORD L. WARREN * PAUL A. WEISS * M. C. WINTER-NITZ * JOHN B. YOUMANSPrice, 2 volumes $15.00 at your medical bookstore or from

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IT'S ACCURATEPrecise fine controls. Multiturn linearpotentiometers allow resetability to 0.1 percent.All parameters are stable to percent orbetter over long periods.

IT'S DEPENDABLEDesigned to be virtually independent oftube changes or circuit ageing.

IT'S RELIABLECalibrated for DIRECT READING using simplemultiplying factors. "Lock-Tite" fine-controldials prevent accidental change of settings. ONE AEL "104" gives

you FOUR modes of operationIT'S RUGGED without using external synchronization25 watt output at 250 volts permitting DIRECT or control systems:use of accessories through Front-Panel-Plug, 1. SINGLE SHOCKS.................... 10 ,us to 1 secondsuch as the AEL 112 ISOLATOR, various magnetic 2 REPETITIVE STIMULI 0.1 cps to 10 kc/sdevices and many other special purpose elements. 2. REPETTRIV STIMULI.0.1 cps to 10 kc/s3. SINGLE TRAINS OR PAIRS OF STIMULI..100 ,us to 10 secondsStimulus output is reversible by front panel switch. 4. REPETITIVE TRAINS OR PAIRS OF STIMULI 100 ius to 10 sec.

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* Phenylindandione* 2-Phenylindole* Phenyllactic Acid* Phenylmercuric Borate* Phenylmercuric Lactate* ,B-Phenylserine* Phenylthienyl Ketone* 9-Phenyl-2,6,7-tri-

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Cobaltinitrite* PotassiumCobaltothiocyanate

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Ask for our newcomplete catalogue

25 NOVEMBER 1955

AAAS SYMPOSIUM VOLUMES(6 x 9 inches, illustrated, clothbound)

The Luminescence of Biological Systems.466 pages ............ ................ $7.00

Advances in Experimental Caries Research.246 pages ............................. 6.75

Antimetabolites and Cancer. 318 pages .... 5.75Fluoridation as a Public Health Measure.240 pages .................. .......... 4.50

Sex in Microorganisms. 362 pages ........ 5.75Astronomical Photoelectric Photometry.

147 pages .................. .......... 3.75The Present State of Physics. 271 pages .... 6.75Monomolecular Layers. 215 pages ........ 4.25Soviet Science. 115 pages ....... ......... 1.25Industrial Science (paperbound). 152 pages 2.00

(7'/2 x 10½ inches, double column, illus., cloth bound)Centennial. 320 pages ........ .......... 5.00Rickettsial Diseases of Man. 255 pages .... 6.25Mammary Tumors in Mice. 231 pages .... 3.50Approaches to Tumor Chemotherapy.

442 pages .................. .......... 7.75

AMERICAN ASSOCIATION FOR THEADVANCEMENT OF SCIENCE

1025 Connecticut Avenue, NW,Washington 6, D.C.

C I

1031